Systems and methods for endoluminal valve creation

ABSTRACT

Medical systems, devices and methods for creation of autologous tissue valves within a mammalian body are disclosed. One example of a device for creating a valve flap from a vessel wall includes an elongate tubular structure having a proximal portion and a distal portion and a longitudinal axis; a first lumen having a first exit port located on the distal portion of the elongate tubular structure; a second lumen having a second exit port located on the distal portion of the elongate tubular structure; a recessed distal surface on the distal portion of the elongate tubular structure, wherein the recessed distal surface is located distally to the first exit port; and an open trough on the recessed distal surface extending longitudinally from the first exit port.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/596,190 filed Feb. 7, 2012 and titled “Valve Creation Mechanism” andU.S. Provisional Application No. 61/665,295 filed Jun. 27, 2012 andtitled “Side by Side Visualization and Associated Mechanisms andFunctions”, which are hereby incorporated by reference in theirentireties for all purposes.

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

FIELD

Embodiments of the present invention relate generally to medicalsystems, devices and methods for creation of autologous tissue valveswithin a mammalian body.

BACKGROUND

Venous reflux is a medical condition affecting the circulation of blood,such as in the lower extremities or neck. The valves in the vessel thatnormally force blood back towards the heart cannot function properly. Asa result, blood flows backwards, causing unwanted clinical problems suchas ulceration or even multiple sclerosis when chronic cerebrospinalvenous insufficiency is present. Applicant of the subject applicationdetermines that new systems and methods for treating venous reflux wouldbe desirable.

SUMMARY OF THE DISCLOSURE

The present invention relates generally to medical systems, devices andmethods for creation of autologous tissue valves within a mammalianbody.

In some embodiments, a device for accessing a valve creation site on avessel wall is provided. The device can include a handle; an elongatetubular structure having a proximal end and a distal end, wherein theproximal end of the elongate tubular structure is attached to thehandle, wherein the elongate tubular structure is sized and configuredfor insertion into a vessel of a patient; and a valve navigationmechanism extending from the distal end of the elongate tubularstructure, wherein the valve navigation mechanism has a smallercross-sectional profile than the elongate tubular structure.

In some embodiments, the handle has a configuration that doubles backtowards the distal end of the elongate tubular structure.

In some embodiments, the valve navigation mechanism is thinner and has asmaller diameter than the elongate tubular structure. In someembodiments, the valve navigation mechanism is more flexible than theelongate tubular structure. In some embodiments, the valve navigationmechanism has an elongate body that is curved along its length. In someembodiments, the valve navigation mechanism has an atraumatic tip.

In some embodiments, the device further includes a tool lumen extendingthrough the elongate tubular structure, the tool lumen having an exitport located on a first side of a distal portion of the elongate tubularstructure.

In some embodiments, the device further includes an expansion elementaligned with the exit port and located a second side of the distalportion of the elongate tubular structure, wherein the first side isopposite the second side.

In some embodiments, the device further includes a predetermined off-setbetween the exit port and a recessed distal surface on the distalportion of the elongate tubular structure, wherein the recessed distalsurface is located distally to the exit port. In some embodiments, therecessed distal surface is flat. In some embodiments, the off-set isramped. In some embodiments, the off-set is less than 2 mm.

In some embodiments, the device further includes a puncture elementextending out of the exit port, wherein the predetermined offset isconfigured to control the depth of penetration of the puncture elementinto the vessel wall, wherein the depth of penetration is less than thethickness of the vessel wall. In some embodiments, the puncture elementcomprises an expansion mechanism. In some embodiments, the expansionmechanism is a balloon. In some embodiments, the puncture element has anasymmetrical tip.

In some embodiments, a device for creating a valve flap from a vesselwall is provided. The device can include an elongate tubular structurehaving a proximal portion and a distal portion and a longitudinal axis;a first lumen having a first exit port located on the distal portion ofthe elongate tubular structure; a recessed distal surface on the distalportion of the elongate tubular structure, wherein the recessed distalsurface is located distally to the first exit port; and a visualizationwindow located on the recessed distal surface.

In some embodiments, the device further includes a visualizationmechanism that is slidably disposed proximate the visualization window.

In some embodiments, the device further includes a flush port located onthe elongate tubular structure proximally to the visualization window,wherein the flush port faces or is tangent to the visualization window.

In some embodiments, the device further includes a flush port located onthe elongate tubular structure distally to the visualization window,wherein the flush port faces or is tangent to the visualization window.

In some embodiments, a device for creating a valve flap from a vesselwall is provided. The device can include an elongate tubular structurehaving a proximal portion and a distal portion and a longitudinal axis;a first lumen having a first exit port located on the distal portion ofthe elongate tubular structure; a second lumen having a second exit portlocated on the distal portion of the elongate tubular structure; arecessed distal surface on the distal portion of the elongate tubularstructure, wherein the recessed distal surface is located distally tothe first exit port; and an open trough on the recessed distal surfaceextending longitudinally from the first exit port.

In some embodiments, the device further includes a visualization toolslidably disposed in the first lumen, wherein the visualization tool isconfigured to have a stowed configuration in which the visualizationtool is contained in the first lumen and an extended configuration inwhich the visualization tool extends from the first lumen and into theopen trough which is configured to guide the visualization tool.

In some embodiments, the device further includes a puncture elementslidably disposed in the second lumen.

In some embodiments, the device further includes a puncture elementidentifier located on a distal portion of the puncture element, whereinthe puncture element identifier is configured to assist in locating thepuncture element.

In some embodiments, the puncture element identifier is selected fromthe group consisting of a reflective surface, a light source and anultrasound transducer.

In some embodiments, the open trough has a depth that is between ¼ to ¾of the trough diameter.

In some embodiments, the device further includes a flushing lumen havinga flush port proximate the first exit port and the second exit port.

In some embodiments, the flushing lumen has a winged configuration.

In some embodiments, the device further includes an expandable elementlocated on the opposite side of distal portion of the elongate tubularstructure than the recessed distal surface. In some embodiments, thedevice further includes an inflation window located on the opposite sideof the distal portion of the elongate tubular structure than therecessed distal surface; a third lumen in communication with theinflation window; and a removable expansion element slidably disposed inthe third lumen.

In some embodiments, a device for creating and fixing a valve leafletfrom a vessel wall is provided. The device can include an elongatetubular structure having a tapered distal end; an expandable elementlocated on a first side of the elongate tubular structure, theexpandable element having a proximal end and a distal end; a sidewaysfacing exit port located on a second side of the elongate tubularstructure between the proximal end and the distal end of the expandableelement, wherein the second side is opposite the first side, wherein thesideways facing exit port is located a predetermined distance from theproximal end of the expandable element; and a lumen in communicationwith the sideways facing exit port; wherein the expandable element isconfigured to create the valve leaflet from the vessel wall whenexpanded from a collapsed configuration to an expanded configurationsuch that the sideways facing exit port is pressed against the valveleaflet.

In some embodiments, the expandable element is configured to create thevalve leaflet from the vessel wall when expanded from a collapsedconfiguration to an expanded configuration such that the sideways facingexit port is pressed against the valve leaflet a predetermined distancefrom a terminating edge of the valve leaflet.

In some embodiments, the expandable element is configured to create thevalve leaflet from the vessel wall when expanded from a collapsedconfiguration to an expanded configuration such that the valve leafletis pressed against another anatomical structure.

In some embodiments, the elongate tubular structure has a distal endwith a tapered portion.

In some embodiments, the tapered portion is asymmetrical and is locatedon the first side of the elongate tubular structure.

In some embodiments, the device further includes a puncture elementdisposed within the lumen, wherein the puncture element contains a valvefixation element.

In some embodiments, the valve fixation element is made of a shapememory material.

In some embodiments, a device for the fixation of two created valveleaflets is provided. The device can include a shaft having a firstlumen and a second lumen and a longitudinal axis; a first tong extendingfrom a distal end of the shaft, wherein the first lumen extends withinthe first tong and terminates in a first inwardly and sideways facingexit port;

a second tong extending from the distal end of the shaft, wherein thesecond lumen extends within the second tong and terminates in a secondinwardly and sideways facing exit port; wherein the first tong and thesecond tong have an opened configuration and a closed configuration,wherein the first port and the second port are aligned within apredetermined distance from each other in the closed configuration.

In some embodiments, the first tong and the second tong are rotatablyattached to the distal end of the shaft.

In some embodiments, the device further includes a fastening mechanismdisposed within at least one of the first lumen and the second lumen. Insome embodiments, the fastening mechanism comprises a deploymentstructure with a suture or a clip.

In some embodiments, a device for accessing a valve creation site on avessel wall is provided. The device can include a handle; an elongatetubular structure having a proximal end and a distal end, wherein theproximal end of the elongate tubular structure is attached to thehandle, wherein the elongate tubular structure is sized and configuredfor insertion into a vessel of a patient; a valve navigation mechanismextending from the distal end of the elongate tubular structure, whereinthe valve navigation mechanism has a smaller cross-sectional profilethan the elongate tubular structure; a tool lumen extending through theelongate tubular structure, the tool lumen having an exit port locatedon a first side of a distal portion of the elongate tubular structure; arecessed distal surface on the distal portion of the elongate tubularstructure, wherein the recessed distal surface is located distally tothe exit port; a predetermined off-set between the exit port and therecessed distal surface; and a puncture element disposed within the toollumen, wherein the predetermined offset is configured to control thedepth of penetration of the puncture element into the vessel wall,wherein the depth of penetration is less than the thickness of thevessel wall.

In some embodiments, a method of creating a valve flap from a vesselwall of a vessel is provided. The method can include providing anelongate tubular structure having a proximal portion and a distalportion and a longitudinal axis, a first lumen having a first exit portlocated on the distal portion of the elongate tubular structure, arecessed distal surface on the distal portion of the elongate tubularstructure, wherein the recessed distal surface is located distally tothe first exit port, and a visualization mechanism located proximate thefirst exit port; inserting the elongate tubular structure into thevessel; advancing the elongate tubular structure within the vessel wall;imaging the vessel wall with the visualization mechanism to identify alocation on the vessel wall suitable for formation of the valve flap;advancing a puncture element through the first lumen and into the vesselwall to a first depth within the vessel wall without penetratingentirely through the vessel wall; and infusing a hydrodissection fluidinto the vessel wall through the puncture element to separate a portionof the vessel wall into two layers and form a hydrodissection pouch.

In some embodiments, the method further includes infusing a fluid intothe vessel to dilate the vessel and increase the tension on the vesselwall.

In some embodiments, the puncture element has a beveled tip.

In some embodiments, the method further includes rotating the beveledtip to control the advancement of the puncture element into the vesselwall to the first depth.

In some embodiments, the method further includes pressing the recesseddistal surface into the vessel wall to control the formation of thehydrodissection pouch.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe claims that follow. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIGS. 1 a-1 b illustrate various views of an embodiment of a device foraccessing a valve creation site.

FIGS. 2 a-2 b illustrate other embodiments of a device for accessing avalve creation site with alternative handle configurations.

FIGS. 3 a-3 b illustrate various embodiments of a device for accessing avalve creation site.

FIGS. 4 a-4 d illustrate the use of an embodiment of a device foraccessing a valve creation site to access the valve creation site andgain wall apposition.

FIGS. 5 a-5 b illustrate an embodiment of a device having a flexiblestructure for accessing a valve creation site that can be straightenedwith a stiffening mechanism.

FIGS. 6 a-6 b illustrate another embodiment of a device having aflexible structure for accessing a valve creation site that can bestraightened with a stiffening mechanism.

FIG. 7 illustrates another embodiment of a device for accessing a valvecreation site.

FIGS. 8 a-8 b illustrate another embodiment of a device for accessing avalve creation site that has a pull wire to manipulate the distal end ofthe device.

FIGS. 9 a-9 b illustrate another embodiment of a device and method forstraightening out and tensioning a vessel wall.

FIG. 10 illustrates an embodiment of a device having an expansionelement.

FIGS. 11 a-11 b illustrate another embodiment of a device having anexpansion element.

FIGS. 12 a-12 b illustrate yet another embodiment of a device having anexpansion element.

FIGS. 13 a-13 d illustrate an embodiment of a device for accessing avalve creation site that has a tool lumen.

FIGS. 14 a-14 b illustrate an embodiment of a device for accessing avalve creation site that has a puncture element extending from the toollumen.

FIGS. 15 a-15 b illustrate an embodiment of a device for accessing avalve creation site that has a puncture element extending from the toollumen that can be rotated to control the depth of penetration into thevessel wall.

FIGS. 15.5 a-15.5 d illustrate an embodiment of a device that useshydrodissection to separate tissue layers.

FIG. 16 illustrates an embodiment of a valve creation mechanism beinginserted into a vessel wall.

FIG. 17 a-17 b illustrate another embodiment of a valve creationmechanism.

FIG. 18 a-18 d illustrate an embodiment of a flap fixation device andmethod.

FIG. 19 a-19 i illustrate another embodiment of a flap fixation devicethat can be used with an embodiment of a valve creation mechanism.

FIG. 20 illustrates an embodiment of a direct visualization mechanism.

FIGS. 21 a-21 c illustrate various embodiments of a viewing window thatcan be used with a direct visualization mechanism.

FIGS. 22 a-22 b illustrate various embodiments of a visualizationmechanism.

FIGS. 23 a-23 b illustrate various embodiments of a visualizationassisting mechanism involving a flushing lumen.

FIG. 24 illustrates another embodiment of a visualization assistingmechanism.

FIG. 25 illustrates an embodiment of a puncture element identifier.

FIGS. 26 a-26 c illustrate various embodiments of visualization displaysthat communicate the image from a visualization mechanism to the user.

FIGS. 27 a-27 d illustrate various embodiments of ultrasound basedvisualization mechanism.

FIG. 28 illustrates an embodiment of a coupling mechanism to attach anultrasound probe onto the handle of a device for accessing a valvecreation site.

FIG. 29 illustrates an embodiment of a device for determining potentialvalve creation sites that includes a compliant balloon that can befilled with a contrast medium or covered with a piezoelectric arraycircuit.

FIGS. 30 a-30 g illustrate an embodiment of a method for valve creationwhich uses a variety of the devices described herein.

FIGS. 31 a-31 b illustrate an embodiment of a bicuspid valve creationdevice and method.

FIGS. 32 a-33 o illustrate an embodiment of a side by side visualizationmechanism.

DETAILED DESCRIPTION Methods and Devices for Accessing a Valve CreationSite and Gaining Wall Apposition and Tautness

In accordance with some embodiments, an apparatus, such as a vessel wallpuncture device, is described that upon being advanced to the preferredsite within a vessel, manipulates the orientation of a vessel to betterperform a vessel wall puncture. All embodiments described for accessinga valve creation site and gaining wall apposition and tautness (coveringFIGS. 1-9, and all associated text that may or may not describeembodiments depicted in figures), can be used in combination with othercomponents described for full valve creation, including but not limitedto: gaining access into an intra-mural space, use of direct or indirectvisualization methods, creation of an intra-mural pocket, valve mouthopening, and valve securement for full valve creation. An example of oneway in which to combine embodiments to complete the valve creationprocedure is depicted in FIG. 19. The embodiments depicted here can beused in combination with these or similar techniques to create a fullvalve geometry. Another similar example of one way in which to combineembodiments to complete the valve creation procedure is depicted in FIG.30. The embodiments depicted here can be used in combination with theseor similar techniques to create a full valve geometry.

In some embodiments of such an apparatus, as is depicted in FIG. 1 (1 aside view, 1 b for top view), the tubular structure 100 to be insertedinto a vessel is substantially rigid, not flexible. This rigid tubularstructure is connected on the proximal end to a handle 101, which allowsfor ease of insertion of the device. In the embodiment depicted, thehandle 101 takes an orientation such that it doubles back in thedirection of the distal end of the rigid tubular structure 100. This mayallow for easier insertion in the high femoral vein in the presence of alarge abdominal protuberance that may hinder vessel access. In someembodiments, the rigid tubular structure 100 is connected on the distalend to a valve navigation mechanism 102, which helps the device navigateexisting venous valves from above. The valve navigation mechanism 102can be thinner with a smaller diameter than the rigid tubular structure100. Additionally, the valve navigation mechanism 102 may be moreflexible than the tubular structure. Additionally, the valve navigationmechanism 102 may have a slight curvature to it, so that rotation of thetubular mechanism allows for more lateral movement of the tip of thenavigation mechanism, while will assist in finding the opening of avalve. Additionally, the valve navigation mechanism 102 may have anatraumatic rounded tip.

In the embodiment depicted, the apparatus form is catered toward use inthe femoral or popliteal vein, to be accessed from above. In addition,the device can be used in the femoral or popliteal veins, to be accessedfrom below. In addition, the device can be used in other veins and/orother blood vessels and/or other lumens. In one specific aspect of theform depicted, the distal end of the tubular structure 100 curves upwardtoward the handle 101 and flattens out to a strait section 104 nearlyparallel to the axis of the handle 101 shown. The distal end 106 iswhere much of the tissue manipulation will occur. In some embodiments(as depicted in FIG. 1 b), the tubular structure may include a subtlecurved portion 105, which is advantageous for navigating through venousvalves or other types of vasculature. In some embodiments, the curvedportion 105 curves laterally with respect to the longitudinal axis L ofthe device. In some embodiments, the curvature of the curved portion 105may have a radius of curvature between 6 inches and 3 ft. In otherembodiments, it may have a radius of curvature between 1 ft and 2 ft. Inother embodiments, it may have a radius of curvature between 1.25 ft and1.75 ft.

Other embodiments shown in FIG. 2, include alternate handle forms, whichprovide various advantages for insertion or manipulation. FIG. 2 adepicts a rigid tubular structure 200 connected to a handle 201 pointingaway from the distal end 202 of the tubular structure. This may beadvantageous in inserting the device in a patient with a relativelyshallow vessel. It also may allow for a large degree of allowedrotation. It also, maybe allow for a better ergonomic feel for the user.It also may be advantageous for passing rigid devices through the handleto the distal end. FIG. 2 b depicts a rigid tubular structure 200connected to a handle 201 pointing upward at about a 90-degree anglewith respect to the shaft of the tubular structure 200. This may beadvantageous in inserting the device in an overweight patient with alarge abdominal section. Other embodiments can have a handle that isangled between about 0 degrees as shown in FIG. 2 a to about 90 degreesas shown in FIG. 2 b.

Other embodiments shown in FIG. 3, show side views of different specificshapes the apparatus may take, all oriented with the handle 300 in thehorizontal position which corresponds to parallel with the supine leg(not depicted). FIG. 3 a shows a tubular structure 303 with a doublebend 301 near the distal end, with an elevated horizontal distalplatform 302 that can be substantially parallel with the handle andlongitudinal axis L. In some embodiments, each bend can have a radius ofcurvature between 0.5 inch and 2 ft. In other embodiments, each bend canhave a radius of curvature between 1 inch and 1 ft. In otherembodiments, each bend can have a radius of curvature between 3 inchesand 9 inches. The elevation D1 of the elevated horizontal distalplatform 302 above the horizontal proximal portion of the tubularstructure 303 can be between about 1 mm to 20 mm. In other embodiments,the elevation may be between 3 mm and 10 mm. In other embodiments, theelevation may be between 4 mm and 7 mm. In some embodiments, D1 can beapproximately equal to the diameter of the vein or blood vessel wherethe surgical procedure, such as valve creation, is to be performed. FIG.3 b shows a tubular structure 303 with a constant downward angle α1 withrespect to the longitudinal axis L. Angle α can be between about 0 to 30degrees, or 5 to 20 degrees, or 10 to 18 degrees. FIG. 3 c shows adouble bend 301 near the distal end, with an elevated but downwardangling distal platform 304. In some embodiments, each bend can have aradius of curvature between 0.5 inch and 2 ft. In other embodiments,each bend can have a radius of curvature between 1 inch and 1 ft. Inother embodiments, each bend can have a radius of curvature between 3inches and 9 inches. The distal platform 304 can be angled at an angleα2 with respect to the longitudinal axis L and can be elevated by aheight D2 with respect to the horizontal proximal portion of the tubularstructure 303. Angle α2 can be between about 0 to 30 degrees, or 5 to 20degrees, or 10 to 16 degrees. The height D2 can be between about 1 mm to20 mm. In other embodiments, D2 may be between 3 mm and 10 mm. In otherembodiments, D2 may be between 4 mm and 7 mm. In some embodiments, D2can be approximately equal to the diameter of the vein or blood vesselwhere the surgical procedure, such as valve creation, is to beperformed.

FIG. 4 depicts an embodiment of use of the entire apparatus 400 in aclinical scenario to access a valve creation site 401 and to gain wallapposition. The form from FIG. 3 a is used in this example, but thismethod of use in the body can be applied to all other apparatusdescribed. FIG. 4 a depicts over-the-wire 405 access which has beenaccomplished at the upper thigh 402, below the ilioinguinal ligament,which is the skin puncture site 403. In other embodiments of the methoda cut down approach may be used. Other potential skin puncture sites 403(not depicted) are: above the ilioinguinal ligament, in the thigh justabove the saphenofemeral junction, in the mid thigh just below thesaphenofemoral junction, in the lower thigh for popliteal vein puncture.A track is made through the skin and tissue down to the vein, at whichpoint a vein puncture site 404 is created using, for example, a needleor trocar with sheath. In some embodiments (not depicted) a punctureelement such as a needle or trocar is incorporated into the front of thedevice itself or is delivered through a through lumen within the device,to be removed after device insertion. FIG. 4 b depicts the apparatus 400being inserted over the wire 405 through both puncture sites 403/404 andadvanced into the femoral 406 and popliteal veins 407. FIG. 4 c depictsadvancement of the apparatus 400 to the distal femoral 406 or poplitealvein 407, so that the distal end is at the valve creation site 401. Ascan be seen, the shape of the rigid apparatus causes apposition of thedevice against the anterior portion of the vein wall 408. The shape andrigidity of the apparatus can also be used to create more wallapposition, by rotating the handle 409 as shown in the figure, such thatthe distal surface of the tubular structure 410 is pivoted upward, witha larger normal force into the anterior surface of the vein 408. Thisaction will force the vein wall to comply with the contour of the distalend of the tubular structure 410. FIG. 4 d depicts a detailed view ofthe distal end of the device, and specifically a particular feature ofits contour, called a recession 412. This recession is a change insurface height on the side of the device to contact the wall. Asdepicted in later embodiments, this recession, allows for the tissue toconform to the contour in a way that allows a device exiting a toollumen 414 to contact the vessel wall at a pre-determined angle α3. Insome embodiments, α3 is between 0 degrees and 45 degrees, or between 10degrees and 35 degrees, or between 15 degrees and 25 degrees.

FIG. 5 a depicts an embodiment that comprises a flexible tubularstructure 500 instead of a rigid one. This structure 500 can be insertedinto a section of a vessel 501 that may contain some element oftortuosity. The tube has within it a communicating lumen 502 that can beused for insertion of a stiffening mechanism 503, which can be advancedtoward the distal end 504 of the flexible tubular structure 500, asshown in FIG. 5 b. This creates a rigidity of the entire device up tothe point of advancement. In some embodiments, the stiffening mechanism503 can be inserted into the flexible tubular structure 500 after theflexible tubular structure 500 has been inserted into the vessel,causing at least a portion of the vessel to conform to the shape of thestiffening mechanism 503. In some embodiments, at least the distalportion of the stiffening mechanism 503 is substantially straight. Inother embodiments, at least the proximal portion of the stiffeningmechanism 503 is substantially straight. In some embodiments, thestiffening mechanism 503 may double as an expansion element orvisualization mechanism of some kind (see embodiments below).

FIGS. 6 a and 6 b depict a similar embodiment, in which the stiffeningmechanism 600 previously described in FIG. 5 includes a slight bend 601on the distal portion to aid in advancing it through a tubular structure602 that has taken at least one bend. The curved stiffening mechanism600 can be rotated at certain bends until a less resistant path is foundto the distal end of the device. The curved section of the stiffeningmechanism may be positioned such that when the stiffening mechanism 600is advanced to the full distal end 603 of the tubular structure 602, astraight section 604 still exists along a sufficient length of vessel605 for certain techniques of tissue manipulation, such as creation ofan autologous valve.

FIG. 7 depicts an embodiment of the rigid tubular structure 700 that hasa short flexible section 701 (about 3 mm to 10 mm in length), whichterminates near the distal portion or distal end 702 (about 25 mm to 75mm) of the rigid tubular structure 700. This allows the device to bemore easily advanced through the vasculature and valves by being able tobend around curvatures in the vasculature. A straight rigid stiffeningmechanism 703 can be advanced through a communicating lumen 704 tostraighten out this flexible section 701 when appropriate. In othersimilar embodiments, curved stiffening mechanisms (not depicted) can beinserted to causes a specific bend in the flexible section. As describedabove, in some embodiments, the stiffening mechanisms can have a curveddistal portion along with at least one straight section.

In accordance with some embodiments, FIG. 8 a depicts a pull wire 800attached to one side of the flexible distal end 801 of a rigid tubularstructure 802. The pull wire 800 can be threaded through the device suchthat the proximal end of the pull wire 800 remains outside the body andcan be manipulated by the user. As depicted in FIG. 86, when the pullwire 800 is retracted, the distal end 801 of the structure is pivotedupward, causing a larger normal force onto the anterior surface of thevein wall 803. This action will force the vein wall to comply with arecession at the distal end of the tubular structure (not depicted inthis figure).

FIG. 9 depicts a different method for straightening out and tensioning avessel wall 900 in which an exit port 901 at or near the distal end ofthe tubular structure 902, which is in fluid communication with a fluidsource 903, is used to inject a large amount of saline or another fluidinto the vessel with enough flow to cause the vessel wall 900 to dilate.In many embodiments, this method can be employed in the venous systemabove or near an existing valve 904. This method can be used inconjunction with any of the other methods and devices described withwhich a taut vessel wall is advantageous. In one particular example,this method can be used in conjunction with a puncture device topenetrate a vessel wall 900. In other examples, the devices describedabove can include a fluid delivery channel and exit port for deliveringfluid into the vessel.

Expansion Elements

The following embodiments describe mechanisms that expand from a tubularstructure and force the other side of the tubular structure into thevessel wall, which may aid in further procedural steps. All embodimentsdescribed for expansion elements (covering FIGS. 10-12, and allassociated text that may or may not describe embodiments depicted infigures), can be used in combination with other components described forfull valve creation, including but not limited to: locating a valvecreation site, hydrodissection, gaining access into an intra-muralspace, use of direct or indirect visualization methods, creation of anintra-mural pocket, valve mouth opening, and valve securement for fullvalve creation. An example of one way in which to combine embodiments tocomplete the valve creation procedure is depicted in FIG. 19. Theembodiments depicted here can be used in combination with these orsimilar techniques to create a full valve geometry. Another similarexample of one way in which to combine embodiments to complete the valvecreation procedure is depicted in FIG. 30. The embodiments depicted herecan be used in combination with these or similar techniques to create afull valve geometry.

FIG. 10 depicts the rigid tubular structure 1000 with an expansionelement 1001, which protrudes off of the opposite side as the tool lumenexit port 1002. In the embodiment shown, the center of the expansionelement 1003 in the longitudinal axis is nearly lined up with the exitport 1002 of the tool lumen. In other embodiments, the center point ofthe expansion element 1003 may be distal or proximal to the exit port1002 of the tool lumen. In embodiments in which the expansion element isa balloon, an inflation lumen exists (not depicted). In some embodimentsof the method, the expansion element 1001 is activated once theapparatus has advanced such that the distal end of the tubular structure1004 is at the valve creation site 1005. This action will force the veinwall to comply with the recession at the distal end of the tubularstructure 1006 and positions the tool lumen exit port 1002 proximal toor against the vein wall.

In some embodiments, the expansion element 1001 is a complaint orsemi-compliant balloon bonded directly to the rigid tubular structure1000 (as shown in FIG. 10).

In some embodiments, the expansion element 1001 is a metal cage or wiremade from a shape memory metal such as Nitinol.

FIG. 11 depicts an alternate embodiment of the tubular member 1100 withexpansion mechanism 1101, which comprises a complaint or semi-complaintballoon bonded to a 360 degree or cylindrical protrusion 1102 from therigid tubular structure 1100, such that a balloon can be bondedcircumferentially at the proximal end 1103 and the distal end 1104 ofthe protrusion 1102, and such that the expansion of the balloon is onlypermitted in the direction opposite the tool lumen exit port 1105 (FIG.11 b). An inflation lumen 1106 is present for activation of theexpansion element.

FIG. 12 a depicts an alternate embodiment of the tubular structure 1200with expansion mechanism 1201, which comprises an expansion mechanismlumen 1202 through which a replaceable compliant or semi-compliantballoon or metallic expansion mechanism can be inserted and advanced.The replaceable balloon or metallic expansion mechanism can be attachedto the distal portion of a tubular support structure 1205 which can beinserted into the expansion mechanism lumen 1202. Distally, an inflationwindow 1203 exists on the bottom side of the tubular structure 1200opposite the tool lumen exit port 1204, such that upon inflation, theexpansion mechanism 1201 is forced to expand out of the inflation window1203 in the direction opposite the exit port of the tool lumen 1204.FIG. 12 b depicts one alternate approach to executing this embodiment,which includes an expansion mechanism 1201 folded on the outside ofanother hollow tubular support structure 1205, with a bonding agent orshrink wrap tubing 1206 sealing off both ends of the expansion member.In this embodiment, the hollow lumen 1207 of the tubular supportstructure can be used to introduce other tools such as a visualizationmechanism.

In some embodiments, the entire distal end of the rigid tubularstructure 1200 is made from a stiff silicone, and a silicone balloonwhich acts as the expansion element 1201 is bonded to the distal end ofthe rigid tubular structure 1200. This can be made in any of thepreviously discussed configurations.

In some embodiments, a through lumen exists within the expansionelement, which can act as a guidewire lumen if a Seldinger technique isdesired.

Puncture Element, Tool Lumen, and Wall Apposition

All embodiments described puncture elements, tool lumens, and wallapposition specifics (covering FIGS. 13-15, and all associated text thatmay or may not describe embodiments depicted in figures), can be used incombination with other components described for full valve creation,including but not limited to: accessing a valve creation site, use ofdirect or indirect visualization methods, hydrodissection, creation ofan intra-mural pocket, valve mouth opening, and valve securement forfull valve creation. An example of one way in which to combineembodiments to complete the valve creation procedure is depicted in FIG.19. The embodiments depicted here can be used in combination with theseor similar techniques to create a full valve geometry. Another similarexample of one way in which to combine embodiments to complete the valvecreation procedure is depicted in FIG. 30. The embodiments depicted herecan be used in combination with these or similar techniques to create afull valve geometry.

FIGS. 13 a and 13 b depict more detail of another embodiment of theaforementioned rigid tubular structure 1300, which contains within it, atool lumen 1301, which connects to a proximal opening 1302 on or nearthe handle 1303 and a distal exit port 1304. Additionally, the rigidtubular structure 1300 contains a through lumen 1305, which connects toa proximal opening 1306 on or near the handle 1303 and a distal exitport 1307. As can be seen, there exists a step down 1308 at the distalexit port of the tool lumen 1304 between the full diameter body of therigid tubular structure 1300 to the recessed distal surface 1309. FIG.13 c depicts the distal end of the tubular structure from a head onview. In this embodiment it is depicted with a rounded surface 1310 tobetter accept the curvature of a vessel wall. FIG. 13 d depicts asimilar embodiment in which the distal end of the tubular structure isflat 1311, which may better assist other follow-on procedural steps suchas clearing out the visual field and containment of the hydrodissectionbubble.

FIG. 14 a depicts an embodiment, in which the puncture element 1400exists outside the tool lumen exit port 1401 prior to advancement of thedevice to the valve creation location 1402. In this embodiment, thepuncture element 1400 can be retracted to the exact location where wallpuncture is desired (not depicted), at which point it is advanced intothe wall 1403 (FIG. 14 b). In this particular embodiment, the punctureheight 1404 is determined by the diameter of the puncture element 1400itself, as well as the bevel geometry and angular orientation of thepuncture element 1400. In some embodiments the puncture height 1404 canbe between about 0 mm and 3 mm, or 0.2 mm and 1.5 mm, or 0.3 mm and 0.8mm, or 0.4 mm and 0.6 mm. This is true because the wall appositioncreated by the device forces the vessel wall 1403 to conform around thepuncture element 1400.

FIG. 15 depicts a method for controlling the depth of the punctureelement 1500 within the vessel wall during vessel wall puncture and/oradvancement of the puncture element within the vessel wall 1501, withrotation of the bevel 1502 of a puncture element 1500. FIG. 15 a depictshow the puncture element 1500 can exhibit forward advancement that tendsoutward, toward the adventitia 1503 if the bevel 1502 is oriented upwardand away from the vessel wall. FIG. 15 b depicts how a rotation suchthat the bevel 1502 is oriented downward toward the intima 1504, cancause the advancement to change course to a more inward path. Anglesbetween these two extremes can be used for more subtle adjustments. Insome embodiments (not pictured) a simple dial can be incorporated intothe handle to adjust the rotation of the bevel, which intuitivelycommunicates to the user how to tweak for conservative (shallow) oraggressive (deep) puncture or advancement. Also, such a technique may beespecially advantageous if used in conjunction with a visualizationmechanism (see later embodiments).

Hydrodissection

All embodiments described for hydrodissection (covering FIG. 15, and allassociated text that may or may not describe embodiments depicted infigures), can be used in combination with other components described forfull valve creation, including but not limited to: locating a valvecreation site, creating wall apposition, gaining access into anintra-mural space, use of direct or indirect visualization methods,creation of an intra-mural pocket, valve mouth opening, and valvesecurement for full valve creation. An example of one way in which tocombine embodiments to complete the valve creation procedure is depictedin FIG. 19. The embodiments depicted here can be used in combinationwith these or similar techniques to create a full valve geometry.Another similar example of one way in which to combine embodiments tocomplete the valve creation procedure is depicted in FIG. 30. Theembodiments depicted here can be used in combination with these orsimilar techniques to create a full valve geometry.

As is described in previous invention disclosures, advancement of thepuncture device can be assisted with infusion of a fluid within theintramural space. In some embodiments, a constant flow of fluid isutilized, such that the same flow rate is ejected from the punctureelement at all times. In other similar embodiments, a mechanism onlyallows fluid to be ejected during the advancement of the punctureelement. In other embodiments, the flow rate can be variable and can beadjusted depending on one more parameters, such as the pressure withinthe vessel or the diameter of the vessel. All embodiments introduced inthis invention disclosure can be utilized with previously describedtechniques for use of hydrodissection to gain access to the intramuralspace, or to create the full pocket geometry necessary for valvecreation.

In an alternate embodiment of hydrodissection, a technique of tissuesoaking is described. In this embodiment, a tissue bulking solution suchas water for injection, D5W (mixed with glucose), or another solutionwith low salinity, i.e. a hypotonic solution, is infused into anisolated segment of a vessel. This can be done by inflating two balloonsdistal and proximal to a potential site, and removing the indwellingblood during infusion of the tissue bulking substance. This solution isallowed to soak the vessel wall for enough time that the tissue expands.Such time may be between 5 seconds and 20 minutes, or between 10 secondsand 5 minutes, or between 20 seconds and 1 minute. This tissue expansionwill create a thicker vessel wall and thus will facilitate thetechniques described for intramural access.

In some embodiments of the invention, a mechanism for controlling thedirection of propagation of a hydrodissection pocket is used. FIG. 15.5a depicts a rigid tubular structure 1500′ with distal end 1502′comprised of a specific cross sectional geometry (FIG. 15.5 b) withcornered edges 1504′ on the side opposite an expandable balloon 1506′(or other expansion mechanism). In this way, when the balloon 1506′ isinflated, the flat surface 1508′ of the rigid tubular structure 1500′ isforced into the vessel wall 1510′ in a way that pinches vessel layerstightly together (compressing the wall thickness) along the lines ofcontact corresponding to the cornered edges 1504′. This occurs along twoparallel lines that extend the length of the rigid distal end 1502′.FIG. 15.5 a shows a puncture element 1512′ emerging from a distal exitport 1514′ of a tool lumen, which is submerged within a vessel wall1510′. The figures also show a hydrodissection agent 1516′ which hasbeen injected through the lumen of the puncture element 1512′ whichforces tissue layers apart within the vessel wall 1510′ to create adissection pocket 1517′. As the agent is injected within the twoparallel lines of pinched vessel wall, the dissection pocket 1517′ isforced to propagate forward along the length of the vessel wall, as thepinched off lines create a seal and prevent circumferential propagationof the dissection. The geometry of the dissection can thus be dictatedby the dimensions of the rigid distal end 1502′. FIG. 15.5 c depicts thegeometry of hydrodissection pouch that might be created by the devicedepicted (viewing the vessel wall from above). In some embodiments, thecornered edges 1504′ have a radius of curvature (r) between 0″ and 0.1″,or between 0.00″ and 0.01″, or between 0.000″ and 0.005″. The width (w)of the flat surface 1508′ may be between 0″ and 0.25″ or between 0.040″and 0.150″ or between 0.080″ and 0.120″.

FIG. 15.5 d depicts another similar embodiment of the distal end of therigid device 1502′ in cross-section. This embodiment comprises a curvedtransparent viewing window 1518′ set between two cornered edges similarto that shown in FIG. 15.5 b and included for the same general reasons.This mechanism and technique is then used in combination with othermethods and devices described, such as an expansion mechanism,visualization mechanisms and valve creation devices to create anautologous valve.

This mechanisms and techniques described can be used in combination withother methods and devices described, such as a transparent window andvisualization mechanisms, valve creation devices, and valve securementmechanisms to create an autologous valve. An example of this entireprocess is depicted in FIG. 19.

Insertion of Valve Creation Mechanism

Once a puncture element has been introduced into an intramural space toa sufficient depth, a technique is employed to insert a valve creationmechanism into the space. Many embodiments of this technique have beendescribed in previous invention disclosures, all of which can beutilized in combination with new inventions described in thisdisclosure. Additionally, all embodiments described for inserting avalve creation mechanism or balloon (covering FIGS. 16 and 17, and allassociated text that may or may not describe embodiments depicted infigures), can be used in combination with other components described forfull valve creation, including but not limited to: locating a valvecreation site, creating wall apposition, hydrodissection, gaining accessinto an intra-mural space, use of direct or indirect visualizationmethods, creation of an intra-mural pocket, valve mouth opening, andvalve securement for full valve creation. An example of one way in whichto combine embodiments to complete the valve creation procedure isdepicted in FIG. 19. The embodiments depicted here can be used incombination with these or similar techniques to create a full valvegeometry. Another similar example of one way in which to combineembodiments to complete the valve creation procedure is depicted in FIG.30. The embodiments depicted here can be used in combination with theseor similar techniques to create a full valve geometry.

One embodiment consistent with the valve creation technique describedthus far in this application, is an “over the wire” approach toinsertion of a valve creation mechanism, with the puncture elementacting as the “wire” in this description. FIG. 16 depicts a mechanism,which includes a deflated non-compliant balloon 1600, which exists on atube 1601 with a hollow lumen 1602 within, sized to accommodate thepuncture element 1603 with a tight sliding fit. A feather tapered tip1604 at the distal end of the balloon tube 1601 is implemented to assistthe device in entering through the hole 1605 in the intimal wall 1606.This mechanism can be inserted until it reaches the full depth of theintramural pocket 1607, and then it is expanded to form a full valveflap geometry by separating tissue layers and by opening up the intimalhole at the top of the pocket. In the embodiment depicted, the rest ofthe tubular structure is removed prior to advancement of the valvecreation mechanism over the puncture element. This can be done byimplementing a removable luer on the back-end of the puncture element1603, so that the entire device can be removed while the punctureelement remains embedded in the vessel wall.

FIG. 17 a depicts an alternate embodiment in which the same techniquefor introducing a valve creation mechanism 1700 (depicted here with adeflated and non-compliant balloon 1703) over the puncture element 1701is utilized, but in this embodiment the valve creation mechanism 1700 isincorporated into the tubular structure 1702 with expansion mechanism1703, so that it can be advanced into the vessel wall without removingthe tubular structure. This is accomplished with a larger diameter toollumen 1704. In this embodiment, the puncture element 1701 is free toadvance separate from the valve creation mechanism 1700 to find thecorrect intramural plane. Then, the valve creation mechanism 1700, whichis pre-loaded onto the puncture element 1701 (as shown), is advancedover the puncture element 1701 as described previously. As can be seen,an off-set 1705 is built in so that the puncture element 1701 remains ata proper puncture height, despite being supported by the lumen 1704 ofthe valve creation mechanism 1700. In some embodiments, the off-set isbetween about 0 mm and 2 mm, or between 0.5 mm and 1.5 mm, or between0.75 mm and 1.25 mm. A flexibility of material is utilized around thistool lumen exit port 1706 and within the valve creation mechanism 1700,to allow it to deform enough to exit the tool lumen exit port 1706 inthe presence of the off-set 1705. FIG. 17 b depicts a similar method ofuse, but the valve creation mechanism 1700 includes an offset punctureelement lumen 1707, so that the off-set 1705 on the tubular structure1702 can be minimized or reduced.

Valve Fixation

Once a valve flap (monocuspid) or two adjacent valve flaps (bicuspid)are created within a vessel, it may be advantageous to affix them to avessel wall or an adjacent valve flap to prevent re-adherance. Allembodiments described for valve fixation (covering FIGS. 18-19, and allassociated text that may or may not describe embodiments depicted infigures), can be used in combination with other components described forfull valve creation, including but not limited to: locating a valvecreation site, creating wall apposition, hydrodissection, gaining accessinto an intra-mural space, use of direct or indirect visualizationmethods, creation of an intra-mural pocket, and valve mouth opening. Anexample of one way in which to combine embodiments to complete the valvecreation procedure is depicted in FIG. 30. The embodiments depicted herecan be used in combination with these or similar techniques to create afull valve geometry.

FIG. 18 depicts one method and mechanism for fixation in a bicuspidvalve creation technique. As depicted in FIG. 18 a, the fixationmechanism 1800 contains two lumens, which extend through the main shaft1801. At the distal end, two hinged tongs extend in a “V” shape from theshaft. One lumen 1802 connects to the left tong 1803, the other lumen1804 connects to the right tong 1805. Both lumens terminate at asideways and inwardly facing exit port 1810, 1812, which are aligned. Inthis method for use, as depicted in FIG. 18 b the fixation mechanism1800 is advanced to align the valve cusps 1806 against a stoppermechanism 1807, which can be located at the base of the v portion of thetongs. This allows for some deviation in longitudinal location of theadjacent valves. At this point, the tongs are closed (depicted in FIG.18 c) to secure the leaflets 1806 in the place. Then, depicted in FIG.18 d, a semi-stiff tube 1808 containing a suture 1809 is pushed throughthe incoming lumen 1802 until it makes the bend and exits the left exitport 1810. The tube has on it a sharp distal end 1811. The sharp point1811 punctures the two leaflets 1806, and is then accepted by anaccepting mechanism 1812 present at the entrance 1813 to the outgoinglumen 1804. Once the sharp tip 1811 is captured, a pull wire 1814pre-loaded in the outgoing lumen 1804 is pulled outward, creating a fullloop of suture (once the stiff tube is removed), that tracks throughboth leaflets. A knot can then be tied form the outside, and can betransmitted through a slot 1815 (FIG. 18 a) between the lumens towardthe leaflets and left in place. A cutting mechanism (not depicted) ispresent to cut the slack ends.

FIG. 19 depicts another similar embodiment for a monocuspid valvefixation technique. As shown in FIGS. 19 a and 19 g, a mechanism forfixing the valve can be disposed within a tool lumen 1908 of the valvecreation mechanism 1902. The valve creation mechanism 1902 is a tubularstructure with a uni-directional balloon 1904 bonded proximally anddistally to one side of the shaft, such that when inflated through aninflation lumen 1906, the balloon 1904 expands outward from one side ofthe valve creation mechanism 1902 (see FIG. 19 b). In some embodiments,the tubular structure can have a tapering distal portion. In someembodiments, the taper can be asymmetrical such that the taperingportion is located on the same side as the balloon 1904. The valvefixation mechanism is delivered through a tool lumen 1908, which isfluidly connected to the proximal end 1910 and a distal exit port 1912.In some embodiments, the tool lumen 1908 can be located within thetubular structure on the opposite side as the balloon such that thedistal exit port 1912 is located at the end of the tapering portion.Additionally, there exists a sideways facing exit port 1914 at alocation opposite the balloon 1904, near the distal end of the tubularmechanism. The sideways facing exit port 1914 may be located between 0mm and 8 mm distal to the most proximal part of the expandable portion1916 of the balloon 1904. Or, it may be located between 1 mm and 5 mmdistal to the most proximal part of the expandable portion 1916 of theballoon 1904. Or, it may be located between 2 mm and 4 mm distal to themost proximal part of the expandable portion 1916 of the balloon 1904.In this embodiment, the tool lumen 1908 doubles as a channel for thepuncture element 1918 and for the valve fixation, mechanism 1900. Inother embodiments, the tubular structure of the valve creation mechanism1902 can have a separate tool lumen 1908 and puncture element lumen (notshown).

As is shown in FIG. 19 c, the puncture element 1918 is used to create adissection pouch 1920 within the vessel wall. As shown in FIG. 19 d, thevalve creation mechanism 1902 is then advanced over the puncture element1918 into the pouch 1920. As shown in FIG. 19 e, the balloon 1904 isthen inflated to create the valvular flap 1922. The device can beoriented with the balloon facing outward, toward the vessel wall 1924,such that the sideways facing exit port 1914 is facing inward toward thelumen 1926. In some embodiments of the method, the balloon 1904 may beoriented inward toward the lumen 1926 upon inflation, and then it isrotated about 180 degrees after inflation. Prior to activating the valvefixation mechanism, the sideways facing exit port 1914 should be apposedto the valvular flap 1922 as shown in FIG. 19 e. At this point, a curvedpuncture element 1928 is advanced to the sideways facing exit port 1914.This puncture element has a sharp distal end 1930, and has a built-incurvature to allow it to exit the sideways facing exit port 1914 whenadvanced. This may be made from a shape memory material such as Nitinol,or from stainless steel or another rigid metal or plastic. In thisembodiment, when the curved puncture element 1928 is advanced, itpunctures through the valvular flap 1922 and through the opposing vesselwall 1932, such that the sharp distal end 1930 extends into or near theextravascular space 1934 (see FIG. 19 f). The valve fixation mechanismalso comprises a pre formed “H” tag implant 1936 and a push rod 1938.The pre-formed “H” tag 1936 is made from a shape memory material such asNitinol, and is forced into an unnatural straight configuration wheninside the lumen of the curved puncture element 1928 (see FIG. 19 g).The pre-formed “H” tag 1936 can be pushed distally with the rigid pushrod 1938. FIG. 19 h depicts what happens as the push rod 1938 isadvanced, and the distal end 1940 of the “H” tag 1936 as it exits thedistal sharp point 1930, and takes its natural barred shape in theextravascular space 1934. FIG. 19 i depicts how upon removal of thecurved puncture element 1928, the “H” tag remains in place, and theproximal end 1942 of the “H” tag 1936 takes its natural barred shape onthe inside of the valvular flap 1922. At this point, the balloon 1904can be deflated, and the entire device can be removed (not depicted),leaving the “H” tag 1936 in place, which acts to prevent the flap fromre-adhering to the vessel wall from which it came.

In another similar embodiment, the curved puncture element 1928 iscurved enough to exit the sideways facing exit port 1914, and re-enteranother sideways facing exit port (not depicted). In this embodiment, asuture is passed through the puncture element 1928, and can be knottedor cauterized or bound into a loop geometry once the curved punctureelement 1928 is passed through the valvular flap 1922 and the vesselwall 1932, and then is re-entered through the valvular wall 1932 andflap 1922 again.

The previously described monocuspid valve fixation techniques could alsobe applied to a bicuspid valve fixation technique, where the valvecreation mechanism 1902 can be used to create a second valvular flapopposite the first valvular flap, and the valve fixation mechanism canbe used to secure the two valvular flaps together. Similarly, thepreviously described valve fixation techniques can be applied to atricuspid valve fixation technique by creating and securing a thirdvalvular flap.

Direct Visualization

In some embodiments of the invention, the use of direct visualizationmay be advantageous during vein access, advancement to the valvecreation site, determination of which valve creation site to use, thevalve creation procedure, and for confirmation of success following theprocedure. The figures shown, display a variety of embodiments. Eachembodiment of the direct visualization mechanism (covering FIGS. 20-22,and all associated text that may or may not describe embodimentsdepicted in figures) can be combined with previously describedembodiments of other features such as locating a valve creation site,creating wall apposition, hydrodissection, gaining access into anintra-mural space, use of indirect visualization methods, creation of anintra-mural pocket, and valve mouth opening, regardless of if they aredepicted in each individual figure. An example of one way in which tocombine these embodiments to complete the valve creation procedure isdepicted in FIG. 19. The embodiments depicted here can be used incombination with these or similar techniques to create a full valvegeometry. Another similar example of one way in which to combineembodiments to complete the valve creation procedure is depicted in FIG.30. The embodiments depicted here can be used in combination with theseor similar techniques to create a full valve geometry.

FIG. 20 depicts the use of a direct visualization mechanism 2000incorporated into the flexible or rigid apparatus 2001 described herein.An additional lumen, called the visualization lumen 2002, is depicted,which allows a visualization mechanism 2000 (depicted here as a flexiblescope) to be advanced up to the distal end of the tubular structure2003. Also, present in this embodiment, is a viewing window 2004 at thedistal end of the tubular structure 2003, which opens upward toward thevessel wall 2005 and extends along the length of the valve creation site2006 to allow for a visualization mechanism that can deflect an image tosome angle to see through the device and into the vessel lumen 2007 andtoward the vessel wall 2005. Deflection angle, α4, is the angle that thecenter of the visual field takes with the axis of the distal end of thetubular structure (which is more or less parallel to the vessel wall). A0 degree deflection would correspond to visualization close to a head onview (straight down the lumen of the vessel). A 90-degree deflectionangle (as depicted in FIG. 20), refers to an angle of visualization thatis directly perpendicular to the vessel wall. In some embodiments, α4can be between 0 degrees and 145 degrees, or between 8 degrees and 120degrees, or between 30 degrees and 90 degrees, or between 50 degrees and75 degrees.

In some embodiments, the visualization mechanism 2000 can be a fiberoptic device.

In some embodiments, the visualization mechanism 2000 can be a rod andlens system, rigid device.

In some embodiments, the visualization mechanism 2000 can be advancedand retracted along the distal end of the tubular structure to adjustthe viewing location.

In other embodiments, the rigid apparatus 2001 takes a linear form, witha visualization lumen 2002, such that off-the-shelf rigid scopes can beinserted up to the viewing window 2004 for use with this device.

In other embodiments, the tubular structure is flexible or has aflexible section, but is made stiff by insertion of a rigidvisualization mechanism 2000.

In some embodiments, the visualization mechanism used allows for a90-degree deflection angle on the line of sight near the distal end ofthe mechanism. Other embodiments may utilize a 45-degree deflectionangle. Other embodiments may utilize a 30-degree deflection angle. Otherembodiments may utilize any other deflection angle between 0-degrees and180-degrees, inclusive.

FIG. 21 depicts different embodiments of the viewing window 2100described. FIG. 21 a depicts a viewing window 2100 that is simply a slotor hole in the rigid tubular structure itself 2101. FIG. 21 b depictsthe use of a transparent plate or film 2102 made of glass, plastic oranother transparent material, which rests within the viewing window 2100flush or nearly flush with the rest of the surface of the tubularstructure 2103. This transparent plate 2102 can act as a transparentmedium for viewing as well as a landing area for the vessel wall to restduring the puncture process. FIG. 21 c depicts an embodiment in whichthe distal end of the tubular structure 2104 is itself made from atransparent material.

FIG. 22 a depicts an embodiment in which the visualization lumen 2200has an open distal end 2201. In this way, a forward facing visualizationmechanism (not depicted) may be advanced to the very distal end of thedevice 2201, or past the distal end of the device to see forward. Thismay be beneficial for navigating through existing venous valves. Then ata different time, the forward facing visualization mechanism can beremoved and an angled visualization mechanism 2202 can be inserted tothe viewing window 2203 to view the vessel wall during the procedure.Also in this figure, there exists an angled visualization mechanism 2202(shown as a rigid scope) attached to a blood stopper 2204 at its distalend, which may be beneficial for flushing blood from the visualizationlumen 2200, and for preventing blood from entering the lumen, in thisparticular embodiment. FIG. 22 b depicts an alternate similarembodiment, in which a clear forward facing window 2205 exists at theend of the open front end 2201 of the visualization lumen 2200, to allowfor forward facing direct visualization 2206 without allowing for bloodor other foreign fluids to enter the visualization lumen 2200. Alsoincluded in this embodiment is a forward facing flush lumen 2207, shownhere with an exit port 2208 directly below the clear forward facingwindow 2205. This would allow the user to flush clear saline in front ofthe forward facing visualization mechanism 2206 to aid in seeing throughopaque blood. Additionally this lumen 2207 could double as a guidewirelumen to further assist in access.

Direct Visualization Assisting Mechanisms

Due to the opacity of blood, direct visualization may require an assistmechanism to help clarify the field of view. All embodiments describedfor assisting in direct visualization (covering FIGS. 23-26, and allassociated text that may or may not describe embodiments depicted infigures), can be used in combination with other components described forfull valve creation, including but not limited to: locating a valvecreation site, creating wall apposition, hydrodissection, gaining accessinto an intra-mural space, use of indirect visualization methods,creation of an intra-mural pocket, valve mouth opening, and valvefixation. An example of one way in which to combine these embodiments tocomplete the valve creation procedure is depicted in FIG. 19. Theembodiments depicted here can be used in combination with these orsimilar techniques to create a full valve geometry. Another similarexample of one way in which to combine embodiments to complete the valvecreation procedure is depicted in FIG. 30. The embodiments depicted herecan be used in combination with these or similar techniques to create afull valve geometry.

FIG. 23 a depicts a visualization assisting mechanism involving aflushing lumen 2300, which is fluidly connected to a flushing fluidsource proximally and a flushing lumen exit nozzle or port 2301 at ornear the distal end of the rigid tubular structure 2302. In theembodiment depicted, the fluid is flushed across the viewing window 2303from its distal end toward the tool lumen exit port 2304 in a proximaldirection. This flushing direction may be advantageous, as it is in thedirection of blood flow, and may aid in clearing the visual field.

FIG. 23 b depicts a visualization assisting mechanism involving aflushing lumen 2300, which is fluidly connected to a flushing fluidsource proximally and a flushing lumen exit nozzle 2301 at or near thedistal end of the rigid tubular structure 2302. In the embodimentdepicted, the flushing lumen 2300 is right next to the tool lumen 2305and fluid is flushed across the viewing window 2303 from its proximalend toward the distal end of the device. This flushing direction may beadvantageous, as it is may be very easy to incorporate into themanufacturing design.

In another embodiment of a device and a method of use (not depicted), avisualization assisting mechanism is embodied by a flushing lumen 2300,which is the same as the tool lumen 2305, and a flushing lumen exitnozzle 2301 which is the same as the tool lumen exit port 2304. In thisway, the act of hydrodissection, or a flushing of the lumen prior to,during, and after puncture can be used to clear the field of view. In asimilar embodiment, flushing is done through the puncture element itself(not depicted).

In another embodiment (not depicted), a flushing lumen exit nozzle 2301exists beside the viewing window 2303, such that a flush can occuracross the window in a perpendicular direction to the direction of thepuncture element movement. This may be advantageous for clearing bloodthat is trapped between the window 2303 and the vessel wall.

FIG. 24 depicts an embodiment in which two expansion elements 2400/2401and a fluid removal lumen 2402 are used to evacuate a segment of vessel2403 of blood. As is shown, the two expansion elements 2400/2401(depicted as balloons) are expanded proximal and distal to the valvecreation site 2404. At that point blood is removed from the vesselbetween the balloons through the suction lumen exit port 2405 with thepresence of a negative pressure source fluidly connected to the suctionlumen 2402. As blood is evacuated, saline or another clear fluid isintroduced through an infusion channel 2406 or the puncture element 2407at the same rate into the vessel, such that the vessel maintains itsdilated form, but the fluid is transparent for viewing purposes.

FIG. 25 depicts a puncture element identifier 2500, which helps the usersee where the tip of the puncture element 2501 is, even if it is withinthe vessel wall 2502. In the embodiment shown, the puncture elementidentifier 2500 is a small light source such as an LED or the output ofa fiber optic cable 2503. The identifier may reside at the base of thebevel (as shown), or somewhere else along the bottom shaft of thepuncture element 2501, within about 3 mm of the distal end. In this way,a direct visualization mechanism, shown here as an angled scope 2504looking through a transparent window 2505, which is in contact with thevessel wall 2502. In another similar embodiment, two or more identifiers2500 are located on different sides of the puncture element. 2501, sothat the puncture element 2501 can be identified no matter what angularorientation it has.

In other similar embodiments, the puncture element identifier 2500 issimply a non-powered reflective surface. In other embodiments, theidentifier 2500 is an ultrasound transducer.

The invention also includes embodiments of visualization displays whichare used to communicate the image from a visualization mechanism to theuser. FIG. 26 a depicts the use of a headset 2600, which displays theimage to the user within the eyepiece 2601 of the set. FIG. 26 b depictsthe use of a small screen 2602 attached to the handle 2603 of thedevice, which displays the image. FIG. 26 c depicts the use of aprojection of the image 2604 from the device onto the patient or anyflat surface 2605 external to the patient. In some embodiments the imageis transmitted wirelessly or through a wired communication to a smartphone or customized mobile device, with sterilization maintained by aprotective pouch. In some embodiments a stand-alone monitor such as a tvset or another type of mobile capital equipment is used.

Ultra Sound Based Visualization Assisting Mechanisms

In some embodiments, the use of external ultrasound visualization isused for multiple functions including but not limited to determinationof potential valve creation sites, vein access and advancement to thevalve creation site, the valve creation procedure, and for confirmationof success following the procedure. The figures shown display a varietyof embodiments. All embodiments described for ultra sound basedvisualization assisting mechanisms (covering FIGS. 27-28, and allassociated text that may or may not describe embodiments depicted infigures), can be used in combination with other components described forfull valve creation, including but not limited to: locating a valvecreation site, creating wall apposition, hydrodissection, gaining accessinto an intra-mural space, use of direct or indirect visualizationmethods, creation of an intra-mural pocket, valve mouth opening, andvalve fixation. An example of one way in which to combine theseembodiments to complete the valve creation procedure is depicted in FIG.19. The embodiments depicted here can be used in combination with theseor similar techniques to create a full valve geometry. Another similarexample of one way in which to combine embodiments to complete the valvecreation procedure is depicted in FIG. 30. The embodiments depicted herecan be used in combination with these or similar techniques to create afull valve geometry.

FIG. 27 depicts use of an external ultrasound probe 2700, used withspecific settings for optimal resolution in the deep veins or othervessels of choice. As can be seen in FIG. 27 a, the unit is used up anddown the patient's leg 2701 (or over whatever body part is to betreated), until a viable valve creation site is identified. The user maylook for a segment of vessel with a constant or nearly constantthickness wall 2702, as compared to images of planes immediatelyproximal and distal to the current plane. If the user finds an unevenlythickened wall 2703, he/she will know to move to a different location.FIG. 27 b depicts how once the cleanest, most consistent vessel walllocation is identified, a marker 2704 is placed at the correct locationon the skin 2705. At this point, in some embodiments the device isadvanced into the vessel until a positioning handle marker 2706 isaligned with skin marker 2704, where the handle marker 2706 correspondsto the location of the distal end of the device. At this point, the usermay check with ultrasound to confirm that the device is properlylocated. Finally, the probe can be maintained at the correct locationfor the duration of the procedure. In this way, the ultrasound image2708 can be utilized to visualize the patient's vessel 2709 somedistance below the patient's skin 2710. The image can be used todetermine placement of the puncture element 2711 within the vessel wall2712 (FIG. 27 c), size and length of hydrodissection pocket, placementof the valve creation expansion mechanism, execution of valve creationwith expansion mechanism 2714 (FIG. 27 d), execution of valve fixation,and finally evaluation of valve dynamics after creation.

FIG. 28 depicts a coupling mechanism 2800 on the handle 2801 of thedevice, to attach the ultrasound probe 2802, so that the probe 2802 mayalways be located at a useful longitudinal location with respect to thedistal tip of the device 2803. As shown, a set pin configuration 2804allows for small adjustments of this longitudinal location so that otherplanes along the length of the device can be seen.

Other Visualization Techniques

All embodiments described for other visualization techniques (coveringFIG. 29, and all associated text that may or may not describeembodiments depicted in figures), can be used in combination with othercomponents described for full valve creation, including but not limitedto: locating a valve creation site, creating wall apposition,hydrodissection, gaining access into an intra-mural space, use of othervisualization methods, creation of an intra-mural pocket, valve mouthopening, and valve fixation. An example of one way in which to combinethese embodiments to complete the valve creation procedure is depictedin FIG. 19. The embodiments depicted here can be used in combinationwith these or similar techniques to create a full valve geometry.Another similar example of one way in which to combine embodiments tocomplete the valve creation procedure is depicted in FIG. 30. Theembodiments depicted here can be used in combination with these orsimilar techniques to create a full valve geometry.

Alternate embodiments include use of intravascular ultrasound (IVUS) fordetermination of potential valve creation sites, vein access andadvancement to the valve creation site, the valve creation procedure,and for confirmation of success following the procedure.

Other embodiments utilize contrast fluoroscopy for determination ofpotential valve creation sites, vein access and advancement to the valvecreation site, the valve creation procedure, and for confirmation ofsuccess following the procedure.

One specific embodiment for determination of potential valve creationsite can be used in conjunction with contrast fluoroscopy, external orintravascular ultrasound, or direct visualization. FIG. 29 depicts theuse of an ultra-compliant balloon 2900 filled with a contrast medium2901 if necessary for the given visualization technique. This balloon2900 is attached to a support tube 2902 with an inflation lumen. Thesupport tube 2902 is advanced to a vessel segment 2903 of interest andthe balloon 2900 is inflated to a certain pressure, which corresponds toa certain apposition on the vessel wall 2904. Due to its compliantnature, the balloon will conform to the abnormalities on the vessel wall2904 rather than flatten out these abnormalities. In this way, theprofile of the balloon can be used to assess the relative smoothness orroughness of a vein wall segment. This profile can be assessed by any ofthe aforementioned techniques to determine if a location in a vessel isan appropriate valve creation site.

An alternate embodiment of this ultra-compliant balloon is to utilize apiezo-electric array circuit along the surface of the balloon, whichallows for measurement of surface abnormalities on the balloon (whichcorrespond to surface abnormalities on the vessel wall), becausedeformities in the balloon surface (and thus the circuit) cause changesin resistance in the circuit. Other non-mentioned methods fordetermining the shape of such a balloon can be employed to make thissurface smoothness determination.

Monocuspid Valve Creation Device and Method

FIG. 30 depicts a complete method for valve creation, which utilizesmany, but not necessarily all, of the individual embodiments describedin this and other related applications. The circular aspect of thefigures to the right are depictions of the direct visualization thatmight be experienced during that point in the procedure. FIG. 30 adepicts insertion of a rigid tubular structure 3000 into the vessel3001. An open-ended visualization lumen 3002 and a direct visualizationmechanism 3003 are incorporated into this embodiment, as well as a valvenavigating antennae 3004. This configuration is utilized to advance therigid device 3000 through the vasculature. A saline burst (not depicted)is utilized through the visualization lumen periodically to help withvisualization of the surrounding wall and valves 3005. Using thisvisualization a potentially suitable vessel section is chosen forfurther investigations (due to absence of side branches and someevidence of a smooth wall). As depicted in FIG. 30 b, the forward facingvisualization mechanism 3003 is removed. FIG. 30 c depicts a angledvisualization mechanism 3006 that has been introduced into thevisualization lumen 3002. Using periodic saline burst through thepre-loaded puncture element 3007, an image of the adjacent vascular wall3008 can be viewed. The device is moved around and rotated subtly untila suitable patch of vascular wall is confirmed. As depicted in FIG. 30d, the expansion element, depicted here as a balloon 3009, is inflatedto appose the opposite vessel wall 3010, which forces the distal end3011 of the rigid tubular structure 3000 up against the vessel wall 3008for valve creation. As depicted, the puncture element 3007 is advancedinto the vessel wall 3008, which is conformed to the stepped surface ofthe rigid device 3000. This can be viewed under direct visualization asshown. As depicted in FIG. 30 e, the puncture element 3007 is advancedwithin the vessel wall 3008, while expelling a hydrodissection fluid,here saline 3012, to create a sub-intimal space 3013 for the punctureelement 3007 to enter. This can be viewed on direct visualization; andis aided by the puncture element identifier, shown here as a light 3014.FIG. 30 f depicts the removal of the tubular structure 3000 (afterdeflation of the balloon 3009), and introduction of the valve creationballoon 3015 up to the puncture site 3016. The valve creation balloon3015 with tapered tip 3017 is then introduced through the inlet 3016 andto the bottom of the intramural pocket 3018 (not depicted). FIG. 30 gdepicts inflation of the valve creation balloon 3015 to create a valveflap 3019. At this point a valve fixation mechanism is implemented toprevent the flap from re-adhering to the vessel wall. Externalultrasound or direct visualization (by re-inserting the tubularstructure) is used to confirm the valve functionality.

In a slightly different embodiment, the rigid tubular structure is notremoved (as previously described) and direct visualization can beutilized through the valve creation procedure to confirm success of theprocedure in real time.

All embodiments described in FIG. 30 can be used in combination withother components described for full valve creation, including valvesecurement. An example of one way in which to combine embodiments tocomplete the valve creation procedure is depicted in FIG. 19. Theembodiments depicted here can be used in combination with these orsimilar techniques to create a full valve geometry.

Bicuspid Valve Creation Device and Method

The bicuspid valve creation device and method described in the followingtext and depicted in FIG. 31, can be used in combination with othercomponents described for full valve creation, including but not limitedto: locating a valve creation site, use of direct and/or indirectvisualization methods, and valve fixation. An example of one way inwhich to combine these embodiments to complete the valve creationprocedure is depicted in FIG. 19. The embodiments depicted here can beused in combination with these or similar techniques to create a fullvalve geometry. Another similar example of one way in which to combineembodiments to complete the valve creation procedure is depicted in FIG.30. The embodiments depicted here can be used in combination with theseor similar techniques to create a full valve geometry.

FIG. 31 a depicts an embodiment of a bicuspid valve creation device andmethod. The embodiment includes two tool lumens 3100/3101 and two toollumen exit ports 3102/3103, oriented about 180 degrees from each otheras shown. The embodiment also includes an expansion element lumen 3104in the middle. As shown in FIG. 31 b, the embodiment also contains aflat, non-compliant balloon 3105, which expands outward through the twoinflation windows 3106/3107, which are oriented about 180 degrees fromeach other. As shown the balloon 3105 is sufficiently flat such thatwhen a vessel is stretched into a severe ellipse upon expansion, thetaut vessel wall rests flat against the sides of the rigid tubularstructure that house the tool lumen exit ports 3102/3103, such that whenthe puncture elements 3108/3109 are pushed out of the lumens 3102/3103,they contact the vessel wall at a consistent location at the samelongitudinal location on the vessel wall. From here, the valve creationtechnique can be implemented twice, on both sides of the vessel wall.Then, a valve fixation technique can be utilized to affix the two valveflaps together, such as was described previously, to finish theprocedure.

Side by Side Visualization and Associated Mechanisms and Functions

Scope Trough

FIGS. 32 a-32 g illustrate an embodiment of a visualization mechanism3200 that can be incorporated in the distal portion of the elongate bodyof the devices described herein, such as a catheter for example. Thedistal end of the elongate body can have a guide or support structure3202 having a partial cylinder or half pipe channel or trough 3204 withone open side positioned on a stiff flat section 3206 of the supportstructure 3202 surface of the catheter. The diameter of the trough 3204can be slightly larger than the visualization tool in use: between 0.5mm and 5 mm. In some embodiments, the diameter is between 1 mm and 3 mm.In some embodiments, the diameter is between 1.5 mm and 2 mm. In someembodiments, the trough depth is roughly half of the diameter of thetrough.

In other embodiments, the trough depth could vary between ¼ of thetrough diameter as shown in FIG. 32 e and ¾ of the trough diameter asshown in FIG. 32 f.

As shown above, in some embodiments in which the trough depth is morethan half of the trough diameter, the trough walls make up more than 180degrees of an enclosure around the scope within (in some embodimentsbetween about 180 and 270 degrees).

In some embodiments in which the trough depth is more than half of thetrough diameter, the trough walls only curve 180 degrees, but can extendperpendicularly from the flat surface upwards from the two widest partsof the trough (half circular trough bottom with high walls), as shown inFIG. 32G.

Scope Trough Function:

(1) The scope trough 3204 can, function as a guiding mechanism to directthe advancement of a visualization mechanism 3200 in a straight line, asillustrated in FIG. 32 h. This helps to minimize the amount of decisionsthe user must make, as it leaves on one degree of freedom, and is usedfor focused evaluation of a narrow strip of tissue for use as a valvestructure.

(2) Additionally, the trough 3204 provides a stand-off from the tissue,as illustrated in FIG. 32 h. The trough 3204 hides the lower half of thefront surface of the scope 3200 from the tissue, forcing the tissue todrape over the front surface of the scope 3200 at a shallower angle,thus preventing the scope face from directly (or perpendicularly)contacting the vessel wall or other anatomical structures. This preventsblurring or blockage of the visual field and bending of the scope 3200upon further advancement following direct contact with tissue, which mayhappen when using a device without a trough, as illustrated in FIG. 32i.

Modes of Visualization:

The visualization mechanisms described herein can be used to assist withvisualization via direct endoscopic visualization, catheter basedultrasound, catheter based OCT, catheter based MRI, or catheter basedCT.

Lateral Viewing

As illustrated in FIGS. 32 j and 32 k, a support structure 3202 near thedistal end of a catheter can be constructed to support two parallelpaths for a 1) visualization mechanism 3200 disposed in a visualizationlumen 3208 and a 2) tool lumen 3210 (i.e., for vein wall puncture andvalve creation using a puncture element and other tools 3212 describedherein). These two functions run within substantially parallel supportlumens 3208, 3210 through the length of the catheter and exit onto asubstantially flat lateral surface 3206 of the catheter's distal end.The two lumens 3208, 3210 are positioned such that when the needle orpuncture element 3212 is advanced out of the exit port and into thevessel wall, it can be seen laterally by an endoscope or othervisualization mechanism 3200, as long as the scope has sufficiently wideangle of view. Lateral visualization requires the scope lumen 3208 andtool lumen 3210 to be very close together, with minimal distance between0.00″ and 0.01″. In some embodiments, the distance between the scopelumen 3208 and tool lumen 3210 can be between 0.00″ and 0.05″.

As illustrated in FIGS. 32 k-m, an additional feature in thisconfiguration is a protective viewing hood 3214 and a side-wall window3216 between the two parallel lumens 3208, 3210. The protective viewinghood 3214 is configured out of a downward sloping termination of thelumen in which the scope 3200 is advanced to the exit port, and acts toshield the scope face from tissue before or after apposition ballooninflation. The side viewing window 3216 is developed by removal of theseptum or wall which separates the scope lumen 3208 and the tool lumen3210, so that the scope 3200 may see the tip of the puncture element3212 laterally, while maintaining its proximal location within the scopehood 3214, even though the puncture element 3212 itself may be slightlyforward from the tool lumen outlet. This window may be present for thedistal 5-25 mm before the exit port.

Function of Lateral Visualization:

Use of side by side visualization includes, for example: evaluation ofvessel wall prior to needle puncture, monitoring vessel wall puncture inreal time, ruling out vessel reentry after vessel wall puncture andadvancement (this is done by advancing the scope within the trough tocheck for needle re-entry), monitoring balloon insertion in real time,checking out balloon re-entry into lumen following advancement ofballoon, monitoring balloon inflation in real time, and for evaluationof the created valve leaflet.

Efficient Flushing Lumens

In order to monitor certain things with direct endoscopic visualizationin a blood vessel, it is advantageous to have a mechanism to flush thevisual field of blood. Embodiments of the present invention can includetwo flush lumens (above and below the scope lens) as illustrated inFIGS. 32 n and 32 o. In some embodiments as shown, the above flush lumen3218 is stationary with respect to the mobile scope 3200, and takes awinged configuration to promote flow of saline or another flushing fluidout along the surface of the scope 3200 and tool 3212. The lower flushlumen 3220 can be part of the mobile scope 3200, and thus can beactuated with equal efficiency regardless of the scope location.

In other embodiments, the flush lumens 3218, 3220 may both be stationaryto the device, or may both be mobile with the scope 3200. In someembodiments the flush lumen may be annular in shape so that it maysurround the scope nearly or fully 360 degrees around.

In all embodiments with a flushing mechanism, a separate aid may be usedin combination, as illustrated in FIG. 32 n. Prior to flushing thevisual field, an expansion mechanism 3222 (such as a semi-compliantballoon) can be expanded off the opposite side of the catheter as thescope 3200, thus forcing the scope side of the catheter into the vesselwall. In doing this, blood is evacuated from the space surrounding thescope 3200. The flushing mechanisms can still be used after expansion ofthe balloon 3222. It may be sufficient to leave a positive pressure dripbag connected to these lumens, such that blood is unable to enter intothe cavity between the scope 3200 and the vessel wall, as the catheterwill have or may have created a near seal against the wall, and thepositive pressure from the flush lumens 3218, 3220 can prevent intrusionof additional blood following initial flushing.

Variations and modifications of the devices and methods disclosed hereinwill be readily apparent to persons skilled in the art. As such, itshould be understood that the foregoing detailed description and theaccompanying illustrations, are made for purposes of clarity andunderstanding, and are not intended to limit the scope of the invention,which is defined by the claims appended hereto. Any feature described inany one embodiment described herein can be combined with any otherfeature of any of the other embodiment whether preferred or not.

It is understood that the examples and embodiments described herein arefor illustrative purposes only and that various modifications or changesin light thereof will be suggested to persons skilled in the art and areto be included within the spirit and purview of this application andscope of the appended claims. All publications, patents, and patentapplications cited herein are hereby incorporated by reference for allpurposes.

I/We claim: 1-27. (canceled)
 28. A device for creating a dissectionpocket in a human blood vessel, the device comprising: an elongatedshaft having a first portion configured to be intravascularly positionedadjacent a dissection site and a second portion configured to beextracorporeally positioned; a trough extending distally in alongitudinal direction from the first portion of the elongated shaft,wherein the trough includes a bottom portion, sidewalls that extend fromthe bottom portion, and a tissue engaging portion along the sidewalls; alumen extending through the shaft and terminating at a port proximal tothe trough; wherein at least a portion of the tissue engaging portion isconfigured to define at least a portion of a periphery of the dissectionpocket.
 29. The device of claim 28 wherein at least a portion of theport is at an elevation corresponding to an elevation of a top portionof the tissue engaging portion.
 30. The device of claim 28 wherein theport is positioned between the sidewalls.
 31. The device of claim 28wherein the sidewalls are curved.
 32. The device of claim 28 wherein thedevice further includes an expandable member coupled to the firstportion of the shaft.
 33. The device of claim 28 wherein the devicefurther includes an expandable member coupled to the first portion ofthe shaft and configured to be positioned circumferentially opposite thetissue engaging portion.
 34. The device of claim 28 wherein the port isa first port and the lumen is a first lumen, and wherein the devicefurther comprises: a second port positioned between the sidewalls; and asecond lumen extending through the shaft and terminating at the secondport.
 35. The device of claim 34 wherein at least a portion of the firstport is at a first elevation and at least a portion of the second portis at a second elevation different than the first elevation.
 36. Thedevice of claim 34 wherein the second lumen is configured to receive anintravascular visualization device.
 37. The device of claim 34 wherein atop-most edge of the second port is at an elevation that is aligned withor below the tissue engaging portion of the trough.
 38. A device forcreating a dissection pocket in a human blood vessel, the devicecomprising: an elongated shaft having a first portion configured to beintravascularly positioned adjacent a dissection site and a secondportion configured to be extracorporeally positioned; a trough extendingdistally in a longitudinal direction from the first portion of theelongated shaft, wherein the trough includes a bottom portion, sidewallsthat extend from the bottom portion, and a tissue engaging portion alongthe sidewalls; a lumen extending through the shaft and terminating at aport proximal to the trough; wherein at least a portion of the tissueengaging portion is configured to stretch the tissue in a plane at anelevation corresponding to an elevation of at least a portion of theport.
 39. A method for dissecting a wall of a blood vessel, the methodcomprising: intravascularly positioning a treatment device in the vesselat a dissection location, the treatment device including a trough havinga bottom portion, sidewalls that extend from the bottom portion, and atissue engaging portion along the sidewalls; contacting the vessel wallalong at least a portion of the tissue engaging portion; and separatinga portion of the vessel wall into a first layer and a second layer whileretaining apposition of the first layer and the second layer along atleast a portion of the tissue engaging portion.
 40. The method of claim39 wherein contacting the vessel wall along at least a portion of thetissue engaging portion includes expanding an expandable member coupledto the treatment device.
 41. The method of claim 39 wherein separating aportion of the first layer from a portion of the second layer includesejecting fluid between the first layer and the second layer.
 42. Themethod of claim 39, further comprising restricting the flow of fluid toa subintimal space between the sidewalls.
 43. The method of claim 39,further comprising: positioning a puncture element at the dissectionlocation; and puncturing the vessel wall at an elevation correspondingto an elevation in line with or above a top-most portion with the tissueengaging portion.
 44. The method of claim 39 wherein contacting thevessel wall includes pressing the first layer against the second layeralong at least a portion of the tissue engaging portion.
 45. The methodof claim 39 wherein the treatment device includes a port proximal to thetrough, and wherein the method further comprises stretching the vesselwall in a plane at an elevation corresponding to an elevation of atleast a portion of the port.
 46. The method of claim 39 wherein thevessel is a venous blood vessel.
 47. The method of claim 39, furthercomprising stretching the vessel wall across the trough; puncturing thevessel wall at an elevation corresponding to an elevation in line withor above a top-most portion of the tissue engaging portion.
 48. Themethod of claim 39, further comprising forming a dissection pocketbetween a portion of the first layer and a portion of the second layer,wherein the contact between the tissue engaging portion and the vesselwall defines at least a portion of a periphery of the dissection pocket.